John Green

New York Times Bestselling Author, Known for "The Fault in Our Stars," "Looking for Alaska" & "Paper Towns"

Tom Ashbrook

Former Host of NPR's "On Point"

Drew Houston

Co-Founder & CEO of Dropbox

Darius Rucker

Lead Singer and Rhythm Guitarist of the Rock Band Hootie & the Blowfish

Darius Rucker & Wife Beth Split After 20 Years: 'We Have Made the ...

Ethan Zohn

Winner of "Survivor" Africa, 2x Cancer Survivor, Stem Cell Transplant Recipient, Social Entrepreneur, Philanthropist, Cancer Research Advocate, Former Pro Soccer Player, Sports Broadcaster & TV Personality

Cal Ripken, Jr.

President & CEO Ripken Baseball, Inc.; Baseball "Ironman" and Legendary Shortstop from the Baltimore Orioles

Ripken says he's cancer-free after March surgery

Annie Lennox

Singer-Songwriter Known for "Sweet Dreams;" Political Activist & Humanitarian